<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>

<body>
    <script>
        var r = /food./
        var str = 'food='
        console.log(r.test(str));

        var r2 = /[abc]/;
        var str = '23123123123123';
        console.log(r2.test(str));

        var r3 = /abc|123/;
        var str3 = '456abca123';
        console.log(r3.test(str3));

        var str4 = 'kaksdad.kad';
        var r4 = /\./;
        console.log(r4.test(str4));

        var str5 = 'asddfassd()aasa';
        var r5 = /\(\)/;
        console.log(r5.test(str5));

        var str6 = 'asddffa""df';
        var r6 = /\"\"/;
        console.log(r6.test(str6));

        var str7 = 'abc123qwe789ccc';
        var r7 = /(113|zxc|qqq)/
        console.log(r7.test(str7));
    </script>
</body>

</html>